Heater for oil wells



Oct. 13, 1959 A. L. BROWN HEATER FOR on. WELLS Filed April 18, 1958ALBERT L. BROWN ,INVENTOR. 7 y/ ATTORNEY United States Patent HEATER FOROIL WELLS Albert L. Brown, San Antonio, Tex.

Application April 18, 1958, Serial No. 732,409

1 Claim. (Cl. 166--61) This invention relates to improvements in heatersfor oil wells, such as those used for melting paraflin, asphalt andthelike in the well bores. Particularly, the present invention meltsaccumulated paraifin in oil producing earth formations for increasingproduction.

An object of the invention is to provide a heater for use in theproducing zones of oil wells for melting paraffin in the surroundingformation, particularly in shallow wells where the bottom holetemperatures are relatively low.

Another object is to provide apparatus for removing accumulated paraffinfrom the lower end of the oil raising equipment.

A further object of the invention is to reduce or eliminate suchsuspensions of operation and to provide an economical and continuousapplication of heat for preventing the accumulation of deposits referredto.

A particular object of the invention is to provide a relativelyinexpensive heater construction for the described purpose.

Other objects and advantages of the invention will become apparent fromthe following description and the accompanying drawing, wherein:

Figure 1 is a diagrammatic view of an oil well installation embodyingthe features of the invention.

Figure 2 is a broken elevation and sectional view of an exemplary formof the invention, and

Figure 3 is a transverse sectional view taken on line 33 of Figure 2.

The oil well diagrammatically shown in Figure l includes a casing 10,tubing 11 extending downwardly in said casing and having a pump 12connected to the lower end of the tubing. In the drawing, the pump 12 isshown to be of larger diameter than the tubing 11. The casing head 13 isconventional, and is not, therefore, described in detail.

A perforated tube 14 is connected with the lower end of the workingbarrel of the pump 12 and extends downwardly into the well bore 15 andinto the producing formation 16. In the exemplary form of the inventionshown, an additional length of perforated tubing 17 is attached to thelast referred to tubing by means of a fitting 18 and which additionallength of tubing is not perforated along the entire length thereof, asindicated at 19. A cylindrical shell 20, having a round lower end 21,and a closed upper end 22, is suspended on the additional tubing 17 bymeans of a yoke 23. Preferably, the diameter of the shell 20 is onlyslightly less than the inside diameter of the casing 10, thus providingfor the lowering of the shell therethrough, and for positioning theshell as near as possible to the producing formation 16 when installed.-The shell 20 is sealed around the tubing 17 by suitable means, notshown, and provides a closed chamber 24 for the circulation of hotfluids, such ice as water, oil or steam. Other suitable heated fluidsmay be used other than the fluids named. Transverse spaced baflles 25are mounted in the shell 20 and around the closed portion 19 of thetubing 17, and which baflles are provided with openings 26 arranged forcreating a tortuous flow of the heated fluids. The exemplary baflleconstruction, shown in detail in Figure 3, is in the form ofsubstantially square plates 25 having their corners rotated 45 relativeto each other. However, it is to be understood that the openings 26 maybe varied so long as the arrangement provides deflection of the flow ofheated fluids in the shell 20.

A fluid supply line 27 extends downwardly through the casing 10 and intothe lower end of the shell 20; similarly, a return line 28 extends fromthe upper end of the shell 20, through the casing 10, and to the earthssurface. Like the extension tubing 17, the supply and return lines 27and 28 are sealed where they extend through the upper end 22 of theshell 20. Any suitable means may be employed for heating and circulatingthe referred to fluid. As shown in Figure l, a coil heater 29 suppliesthe fluid to a pressure storage tank 30 by means of a pump 31 andconnecting lines 32. The described supply line 27 is connected with thetank 30, whereas the return line 28 is directly connected with the coil33 of the heater 29.

Upon consideration of the foregoing description, it will become apparentthat the circulated heated fluid will not only heat the jacket 20, butwill also heat the extension tubing 17. Also, the baffles 25 act as heatexchangers for conducting heat from the circulating fluid to thecylindrical shell 20 which, in turn, heats the formation 16 and the wellfluids in the bore 15.

It is to be understood that the foregoing description is exemplary andmay be varied by those versed in the art without departing from thescope of the invention as defined in the appended claim.

What is claimed is:

Apparatus for melting parafiin and other deposits in an oil well havinga pump suspended on a tubing in the well bore, said apparatus comprisingan additional length of tubing connected with and depending from saidpump, a closed elongated cylindrical shell mounted around saidadditional length of tubing, the lower end of said additional length oftubing extending beneath said shell where said additional length oftubing is open to the Well, a supply line extending from the earthssurface to the lower interior of said shell, a return line extendingfrom the upper interior of said shell to the earths surface,substantially square transverse baffles projecting from the Wall of saidshell and spaced from each other within said shell between the upper andlower ends thereof, the corners of said baffles being secured to theinner surface wall of said shell, said bafiles being of areas less thanthe transverse area of said shell, adjoining said baflles being rotated45 with respect to each other around said additional length of tubing,and means supplying heated fluid to said supply line.

References Cited in the file of this patent UNITED STATES PATENTS760,304 Butler May 17, 1904 1,959,368 Kennedye May 22, 1934 2,035,381Abele Mar. 24, 1936 2,078,107 Ten Brink Apr. 20, 1937 2,647,585 RobertsAug. 4, 1953 2,705,535 Waterman Apr. 5, 1955

